15 things every LiPo battery user should know

LiPo batteries are generally safer and more environmentally friendly than other R/C batteries like NiCd and NiMH. LiPo batteries have become the most common high performance R/C battery and are used in R/C cars, boats, planes, helis, multirotors and more. However, if charged, discharged, stored, maintained, or handled improperly, they can become extremely dangerous. This is a simple guide for safe LiPo battery ownership and use. This guide applies to all R/C LiPo batteries including all DJI Smart Batteries used in the Phantom 2 series and Inspire 1.

2. Avoid purchasing used LiPo batteries. You never know what the previous owner did with them and they could already be badly damaged. “LiPo Battery Like New, Used Once” is usually a scam and should be avoided.

3. Always use a proper LiPo battery balance charger/discharger when charging and discharging your LiPos. It is crucial that all cells in a LiPo battery maintain the same voltage across all cells at all times. If the voltages across the cells deviate too much from each other (5mV ~ 10Mv), the battery can become unstable and dangerous. (Unless it’s a single cell LiPo, in which case you do not need to worry about cell balance).

4. Always use a fire proof LiPo safety bag, metal ammo box, or other fire proof container when you are charging, discharging, or storing your LiPo batteries. While LiPo fires are rare, they can happen incredibly quickly and can do a lot of damage. All it takes is an internal short circuit to set the battery off. There is no way to predict when it will happen. It does tend to happen more often when batteries are fully charged, being overcharged, or while being discharged, but it can happen to any LiPo at any time. Never fill the container to capacity with your batteries, always follow manufacturer recommendations on LiPo bags for how many mAh’s it can safely contain. It’s ALWAYS worth investing in an (under $10) explosion-proof LiPo bag or ammo can.

5. Do not use your flight case/travel case for long term LiPo storage. The foam and plastic in these cases can help spread a LiPo fire. Always use a fire proof container such as a metal ammo box or fire proof safe for storage.

6. Never leave your LiPo batteries charging while unattended. If a battery starts to become puffy, smoke, or catches fire you need to be able to immediately handle the situation. Walking away for even just 5 minutes can spell disaster.

7. A LiPo fire is a chemical fire. Always keep a Class D fire extinguisher nearby your battery charging/discharging and storage area. The battery charging/discharging and storage area should be free from any materials which can catch fire such as wood tables, carpet, or gasoline containers. The ideal surface for charging and storing LiPo batteries is concrete or ceramic.

8. Never overcharge a LiPo battery. Typically a full charge is 4.2v per cell. Never “trickle” charge a LiPo battery.

9. Never discharge a LiPo battery below 3.0v per cell. Ideally you never want to go below 3.2v per cell to maintain a healthy battery. 2.9v per cell and lower is causing permanent damage.

10. Never leave your LiPo batteries sitting around on a full charge for more than 2-3 days. If by the 3rd day you realize you are not going to use your battery today, you need to discharge your battery down to 3.6v-3.8v per cell for safe storage until you are ready to use the battery again.

11. Always store your LiPo batteries at room temperature. Do not store them in a hot garage, or in a cold refrigerator. Even though a cold battery has less chemical reaction taking place which can prolong its lifespan, taking a battery out from a cold fridge can cause condensation to occur on the inside of the battery, which can be very dangerous.

12. Always remember that heat is the number one enemy of LiPo batteries. The hotter your batteries get, the shorter their lifespan will be. Never charge a battery that is still warm from usage, and never use a battery that is still warm from charging.

13. Depending on how they are used, most LiPo batteries typically do not last longer than 300 charge cycles. Leaving them around on a full or depleted charge all the time, running them completely dead, or exposing them to high temperatures will shorten this lifespan dramatically.

14. LiPo batteries do not work well in cold weather. The colder it is, the shorter your run times will be due to the slowing down of the chemical activity within the battery. If it is below 14F (-10C), LiPo usage is not recommended at all. Your battery could cause your R/C vehicle to suddenly fail without warning in these temperatures.

15. Always pack your LiPo batteries in your carry-on bag and never in your checked baggage when traveling on an airplane. It’s the law.

-Written by Jessika Farrar

Jessika Farrar is the founder of ASG Aerial and specializes in aerial photography for personal and business use. Visit www.ASGaerial.com to learn more, or to book an appointment.

Jessika Farrar is also the Network Administrator for the S.W.A.R.M. Network where thousands of pilots from around the world volunteer their skills to help connect life saving drone technology with missing people. Go to www.SARdrones.org to learn more about how you can help.

Hey Drone Girl, great article and especially important for guys who are not used to dealing with and caring for RC LiPos.

Regarding tip #10 – very true…
I found the lack of a decent way to discharge quickly to storage level quite a problem so I created a little gadget to do just that. I call it the Phantom Angel (because it protects your Phantom 🙂 ) More info at http://phantomangel.rocks

Check your milivolts and megavolts. Capitals do play a role just as significant as temperature tolerances.

And… when you fly on a cold day with a cold battery… doen’s the battery have a momentary increase in internal resistance?
And what does, the increased internal resistance, cuase?
Ain’t it… heat? Which, in turn, causes the internal resistance to increase?

Lipo should not be stored in an air tight metal box, chem fire will not stop burning and can cause internal pressure until it’s released. Metal air tight ammo box in other words becomes a bomb. Maybe videos on YouTube about it.

Unless you have a hole drilled into the ammo box for a pad lock already, if not you drill through the latch part on the sides straight threw the width of the box. Then you should be fine. I use one to store my rc car batteries..

You can if you drill a hole threw the width of box on the sides into the latch. I had one from military school & it already had hole for pad lock. I use it to store my rc car batteries. =) I like it better than a lipo bag it had character. Hope that helps someone with one.

[…] Re: Storing a lipo? Lipo's won't last very long if there not taken care of. If your going to use lipos, there are plenty of inexpensive chargers that will put a battery to a storage voltage which is 3.8 volts per cell. The cheaper batteries won't take much abuse. I try not to leave my lipos fully charged for more than a couple of days. 15 things every LiPo battery user should know | Drone Girl […]

[…] (Of course, check with your airline and airport before traveling with a drone and its accompanying LiPo batteries). I use the same box the Phantom 4 came in as my carrying case. It’s perfect! However, while […]

The LED lights shouldn’t light up again after it’s charged. There’s something wrong with that P4 battery. P4 batteries won’t even let you “top off” the battery like the P3. Normally when a P4 battery is charged it won’t let you charge it any more, the LED lights will not light up again. It’s considered to be a “smart battery”. Visit phantompilots.com, you can learn a lot there.

Jessica, I think your statement of 5 to 10mv is incorrect, by one decimal place. Usually the cell deviation between cells of .07 to .1 volts is when you should be concerned about the battery’s health. That’s 70mv to 100mv.

LiPo batteries offer a wide array of benefits. But each user must decide if the benefits outweigh the drawbacks. For more and more people, they do. In my personal opinion, there is nothing to fear from LiPo batteries, so long as you follow the rules and treat the batteries with the respect they deserve.

That’s how it is: do not store discharged nor fully charged (for days). It does make things more complicated. After use the battery should be charged/discharged to storage voltage. That means, only fully charge the battery when you know you’ll be using it (that day).

Phantom 1 charger didn’t even have such charging option, so I’m using specialized multi purpose LiPo charger now. I don’t have smart batteries.

Captain Obvious would tell you to hover the drone in the same spot until it is discharged enough.
Alternatively, if you have the right adapter, use the drone battery to charge your USB devices until they are drained enough.

I almost caught my house on fire tonight. Was charging 4 5000 22v lipos on the counter top. I knew that one of them had an issue with the balance port. I was getting a Vol Err but was getting other errors too. I decided not to charge with balance port but to just do a regular charge. An hour later my wife comes into my office to tell me one of the batteries is smoking. I ran to the kitchen, turned off the power supply, disconnected the battery and ran to the front door. It burst into flames while in the air after chucking it about 6 feet. 5 foot flame was coming out of both ends of the battery. Hose water did absolutely nothing. Lesson learned. All batteries outside now. If my wife had not seen the battery smoking, it would have been ugly.

Very useful article. Should be compulsory reading for everyone using LiPos. What concerns me is there are now millions of drones out the all using LiPos, many in the hands of kids whose parents bought them for Christmas (guilty) and who have no idea at all of the potential for problems. Serious review of my own charging and storage regimes. Ammo boxes and lipo bags for storage and charging also a second CO2 fire extinguisher, won’t stop the battery but may be enough to suppress anything nearby that manages to catch. Disposal of bloated batteries not discussed here which is an oversight IMHO. I dishcharge with a balance charger down to storage levels, then am currently using a car light bulb to run absolutely flat. All done outside under metal bucket weighted down with bricks. I currently do this as soon as any sign of gas build up in a battery which is annoyingly frequent. Possibly my storage regime has been lax, leaving batteries charged too long.

good info on LiPo batteries. A couple things I’d like add. BTW, I am an engineer and have worked a industrial/medical custom battery pack and charger design/manufacturing firm for several years. I have seen a Li-ion fire first hand in the lab and have designed dozens and dozens of battery packs and chargers for customers.

1) Good tip on the vent in an ammo box. Had not thought about that. I get my drill out and vent mine. I did not stop to think they are water/air tight. When they burn, LiPos generate a tremendous amount of gas and flame. The electrolyte and other internal materials contain fuel AND oxidizer. Inside a latch ammo can, it’s a potential bomb that would make some nasty shrapnel.

2) NEVER put water on a Lipo fire. You will create an explosion. The fire is so hot it will make steam which will then (potentially) disassociate into H2 and 02 and BOOM really big. “Smother the mother” – sand, dirt, etc. and get it the hell out of your house/shop/garage. Very likely it will set something else on fire.

3) Good thing to have on hand: metal garbage can with a tight lid and fill it with sand or vermiculate (gardening section at Home Depot). Throw the pack in the can and slam the lid on. And use a hole saw to make a nice vent “chimney” in the lid.

4) While you are at home depot getting that can, pick up several cheap 12″ ceramic floor tiles. They are what you want to put the pack on when charging or storing. Don’t have the pack on a combustible table/floor/shelf.

5) Fundamentally, LiPos have a small margin when fully charged between max voltage/temp and over voltage/over temp. They have far LESS safety margin and have far MORE electrical energy when fully charged. Pretty much the same level of chemical energy when at low voltage but far, far less electrical energy to make a big spark from an internal short.

2. Avoid purchasing used LiPo batteries. You never know what the previous owner did with them and they could already be badly damaged. “LiPo Battery Like New, Used Once” is usually a scam and should be avoided.

Such blanket statements do not serve the community well. You’re letting your paranoia off the few bad apples in society affect the many and by the comments, I see you’ve already affected some. There are plenty of reason a good seller can be selling a good used battery and as always, should be up to due diligence and not blanket statements.

The rest of it is well done and useful info. Maybe a rephrase of #2 would be in order.

You should add a point saying “don’t believe everything internet tells you”… I’m thinking about “8. Never overcharge a LiPo battery. Typically a full charge is 4.2v per cell. Never “trickle” charge a LiPo battery.” -> LiPo (Lithium Polymer) batteries are meant to be charged to 3.7V, if you’d try 4.2V it’ll likely explode. 4.2V is for Li-Ion batteries (Lithium Ion)… Get your facts straight before posting, especially if you’re trying to help people avoiding accidents..

Nope, I just said some stupid s*** right there. I’ll have the decency to rectify myself before shooting myself in the head. Effectively, both LiPo and LiIon have to be charged to 4.2V. Sorry, had my mind mixed up.

In regard to the types of batteries, it is my understanding the later lithium polymer (LiPo) uses a jell-like electrolyte vs liquid which prevents the battery (unlike the (Li-On) older version from exploding or igniting when punctured, etc. Is that not correct?

LiPo’s are high maintenance, but worth it. The constant power throughout gives me the illusion of a longer run times. Not so much with a nimh that slowly drains and loses that umph near the end. Nice article, great information.

Thanks so much for this article Drone Girl and I have purchased a Fireproof storage bag you had a link for as my son got a lipo battery today and it simply scared the life out of me how volatile they potentially can be. So thanks again your article has put my mind at ease – thanking you!

Awsome article, I’m new to lipo, I just started running them in my RC trucks, is it ok to charge a lipo even if it’s not close to low voltage? I usually run my truck for 30 minutes and then I’ll throw the battery on the charger while I clean up in the garage so I always have a full charge for the next day. Am I doing something I shouldn’t do? Thanks
Sam p

Nicely done article Drone Girl. It’s true that Lithium Polymer batteries are much more safer and eco-friendly. They are considered to be the most efficient battery so far. As one of the latest battery technologies of today, these batteries also offer more capacity, cycles and higher charge rate. Although they are a bit expensive, the great features that they offer overshadows its cost. They can also be charged even if they still a lot charge left in them without risking its life expectancy.

That’s great! I have get a huge info on the lipo battery. Battery is the oxyzen of the drone. So, it’s essential to know the ins and out of the battery. This article gives me that. When charging and when it over charge. I have known a lot. Thanks again.